Matronics Email Lists :: View topic - How to seal Tygon tube to barb fittings

Matronics Email Lists
Web Forum Interface to the Matronics Email Lists

Get Email Distribution Too! FAQ Search Memberlist Usergroups Register

Profile Log in to check your private messages Log in

How to seal Tygon tube to barb fittings

Matronics Email Lists Forum Index -> AeroElectric-List

View previous topic :: View next topic

Author Message

rparigoris

Joined: 24 Nov 2009
Posts: 780

Posted: Tue Apr 27, 2021 10:05 am Post subject: How to seal Tygon tube to barb fittings

Hi Group. I have a mix of instruments that use various Barb fittings. Some 1 barb, some 2 and some more. Anything Winter or from Germany have gorgeous 2 rounded bump barbs. They don't leak at all. Some of the others with some poking I can get to leak. In the soaring community, if using old tubing or if you suspect leaking, they use a Green Latex farm animal castrating donut. I have some and they work great. Size is 5.5mm ID (.217") x 13.5mm OD (.532"). The Tygon tubing I'm using is 9/32"OD (.281") x 5/32"ID (.156") and depending on barb OD will grow in size. I can only use the Latex rings on about 1/4 of my connections because the rings are so thick (.158"). I would like to use dash 105 O-Rings. I tried a gazillion small clamps, nothing tickles my fancy. ID not right size, too much tension and point loading on wire clamps is 1 on bottom and 2 on top. I tried a double wrap of .25" safety wire, kinda OK but very fiddly to get it just right. You want a complete circle and it needs to go between the point of the barbs so has to be very thin. 

Anyway McMaster has A70 durometer dash 105 O-Rings in Buna-N, Viton, Silicone, EPDM and Poly Urethane. They also have harder A90 in Poly Urethane.

Any input on which compound of O-Rings might keep tension better over time when used as a rubber band?

Any other ideas welcomed.

Anyone know of a small circular spring like those used in lips of seals with an approx ID of less than .281"?

Thx. Ron P.

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

ashleysc(at)broadstripe.n
Guest

Posted: Tue Apr 27, 2021 12:08 pm Post subject: How to seal Tygon tube to barb fittings

Hi Ron;

Viton will probably hold up the best.

Oetiker makes corrosion resistant clamps that hold tight, are light weight, require a special tool to install, and are one-time use.

There is a safety wiring tool that encircles the tubing with 4 wraps of safety wire and folds it over to clench. This is lighter than Oetiker and also one-time use. If you are interested in pursuing this, I can get the name off my tool in the hangar.

Cheers!   Stu.



---

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Ceengland

Joined: 11 Oct 2020
Posts: 381
Location: MS

Posted: Tue Apr 27, 2021 12:12 pm Post subject: How to seal Tygon tube to barb fittings

On Tue, Apr 27, 2021 at 1:32 PM rparigoris <rparigor(at)hotmail.com (rparigor(at)hotmail.com)> wrote:



 	  Quote: 	
		  --> AeroElectric-List message posted by: "rparigoris" <rparigor(at)hotmail.com (rparigor(at)hotmail.com)>

 

 Hi Group. I have a mix of instruments that use various Barb fittings. Some 1 barb, some 2 and some more. Anything Winter or from Germany have gorgeous 2 rounded bump barbs. They don't leak at all. Some of the others with some poking I can get to leak. In the soaring community, if using old tubing or if you suspect leaking, they use a Green Latex farm animal castrating donut. I have some and they work great. Size is 5.5mm ID (.217") x 13.5mm OD (.532"). The Tygon tubing I'm using is 9/32"OD (.281") x 5/32"ID (.156") and depending on barb OD will grow in size. I can only use the Latex rings on about 1/4 of my connections because the rings are so thick (.158"). I would like to use dash 105 O-Rings. I tried a gazillion small clamps, nothing tickles my fancy. ID not right size, too much tension and point loading on wire clamps is 1 on bottom and 2 on top. I tried a double wrap of .25" safety wire, kinda OK but very fiddly to get it just right. You want a complete circle and it ne!

  eds to go between the point of the barbs so has to be very thin. 

 Anyway McMaster has A70 durometer dash 105 O-Rings in Buna-N, Viton, Silicone, EPDM and Poly Urethane. They also have harder A90 in Poly Urethane.

 Any input on which compound of O-Rings might keep tension better over time when used as a rubber band?

 Any other ideas welcomed.

 Anyone know of a small circular spring like those used in lips of seals with an approx ID of less than .281"?

 Thx. Ron P.

	
Something like this?

7mm constant tension hose clamp



You'd need to verify it this particular one applies clamping pressure to a 7mm hose, or it's closed size is 7mm. For more options, just google what I wrote as the link text & substitute the size you want. The flat wrapped springs are quite common in Japanese cars, so you should be able to find something that will work.

My personal preference when using hard polyethylene tubing is to use push to connect fittings. They have  a 'rubber' gasket that seals to the *outside* of the tubing, and a metal barb that catches the tubing beyond the sealing point. Easy insertion/removal, unlike barb fittings. Note that you can also find them on ebay, Amazon, etc, usually for a lot less money. If the Tygon you're using is some other, softer material, they probably won't work for you.

Charlie

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

_________________
Charlie

steve(at)tomasara.com
Guest

Posted: Wed Apr 28, 2021 5:11 am Post subject: How to seal Tygon tube to barb fittings

 	  Quote: 	
		   rparigor(at)hotmail.com (rparigor(at)hotmail.com)>



 Hi Group. I have a mix of instruments that use various Barb fittings. Some

 1 barb, some 2 and some more. Anything Winter or from Germany have gorgeous

 2 rounded bump barbs. They don't leak at all. Some of the others with some

 poking I can get to leak. In the soaring community, if using old tubing or

 if you suspect leaking, they use a Green Latex farm animal castrating

 donut. I have some and they work great. Size is 5.5mm ID (.217") x 13.5mm

 OD (.532"). The Tygon tubing I'm using is 9/32"OD (.281") x 5/32"ID (.156")

 and depending on barb OD will grow in size. I can only use the Latex rings

 on about 1/4 of my connections because the rings are so thick (.158"). I

 would like to use dash 105 O-Rings. I tried a gazillion small clamps,

 nothing tickles my fancy. ID not right size, too much tension and point

 loading on wire clamps is 1 on bottom and 2 on top. I tried a double wrap

 of .25" safety wire, kinda OK but very fiddly to get it just right. You

 want a complete circle and it ne!

  eds to go between the point of the barbs so has to be very thin.

 Anyway McMaster has A70 durometer dash 105 O-Rings in Buna-N, Viton,

 Silicone, EPDM and Poly Urethane. They also have harder A90 in Poly

 Urethane.

 Any input on which compound of O-Rings might keep tension better over time

 when used as a rubber band?

 Any other ideas welcomed.

 Anyone know of a small circular spring like those used in lips of seals

 with an approx ID of less than .281"?

 Thx. Ron P.




	




I make a tourniquet using two wraps of lacing cord.  Really easy and seems to work fine.

Steve Stearns

O235 Longeze

Boulder / Longmont CO

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

steve(at)tomasara.com
Guest

Posted: Wed Apr 28, 2021 5:13 am Post subject: How to seal Tygon tube to barb fittings

P.S.  I do the same thing for the fuel-line on barbs on my old BMW motorcycle. 



Works there too even with the scratched up aluminum barbs.

Steve.

On Wed, Apr 28, 2021 at 7:10 AM Steve Stearns <steve(at)tomasara.com (steve(at)tomasara.com)> wrote:



 	  Quote: 	
		  > rparigor(at)hotmail.com (rparigor(at)hotmail.com)>

 	  Quote: 	
		  

 Hi Group. I have a mix of instruments that use various Barb fittings. Some

 1 barb, some 2 and some more. Anything Winter or from Germany have gorgeous

 2 rounded bump barbs. They don't leak at all. Some of the others with some

 poking I can get to leak. In the soaring community, if using old tubing or

 if you suspect leaking, they use a Green Latex farm animal castrating

 donut. I have some and they work great. Size is 5.5mm ID (.217") x 13.5mm

 OD (.532"). The Tygon tubing I'm using is 9/32"OD (.281") x 5/32"ID (.156")

 and depending on barb OD will grow in size. I can only use the Latex rings

 on about 1/4 of my connections because the rings are so thick (.158"). I

 would like to use dash 105 O-Rings. I tried a gazillion small clamps,

 nothing tickles my fancy. ID not right size, too much tension and point

 loading on wire clamps is 1 on bottom and 2 on top. I tried a double wrap

 of .25" safety wire, kinda OK but very fiddly to get it just right. You

 want a complete circle and it ne!

  eds to go between the point of the barbs so has to be very thin.

 Anyway McMaster has A70 durometer dash 105 O-Rings in Buna-N, Viton,

 Silicone, EPDM and Poly Urethane. They also have harder A90 in Poly

 Urethane.

 Any input on which compound of O-Rings might keep tension better over time

 when used as a rubber band?

 Any other ideas welcomed.

 Anyone know of a small circular spring like those used in lips of seals

 with an approx ID of less than .281"?

 Thx. Ron P.




	




I make a tourniquet using two wraps of lacing cord.  Really easy and seems to work fine.

Steve Stearns

O235 Longeze

Boulder / Longmont CO

- The Matronics AeroElectric-List Email Forum -

Use the List Feature Navigator to browse the many List utilities available such as the Email Subscriptions page, Archive Search & Download, 7-Day Browse, Chat, FAQ, Photoshare, and much more:

http://www.matronics.com/Navigator?AeroElectric-List

Display posts from previous:

	Matronics Email Lists Forum Index -> AeroElectric-List	All times are GMT - 8 Hours
Page 1 of 1

Jump to:

You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You cannot attach files in this forum
You can download files in this forum